66 MARINE ALGAL 
waved on margin; substance soft and thin; dotted with spores. In the 
young plants fine hairs emerge from the dots, but disappear later, and 
the fronds become darker and more rigid. Found in summer on rocks 
and on other algee on the Long Island and New England coasts. 
P. tenuissima. Fronds smaller and more slender than in P. latifolia; 
thin and delicate. Found on eel-grass and Chorda filum. 
P. plantaginea. Fronds dark brown, leathery, leaf-like, blunt or 
wedge-shaped on top; dense clusters of hairs on the dots; six to twelve 
inches long, one inch to one and a half inches wide. 
GENUS Asperococcus 
This genus differs from Punctaria in having a tubular instead 
of a flat frond. (Plate IX.) 
A. echinatus. Resembles Enteromorpha in being tubular; compressed’ 
or inflated; obtuse at the apex; attenuated at the base. It differs from 
Enteromorpha in being olive in color, and in being covered with small 
oblong dots of darker shade. When the plant is young the dots are 
hairy. It grows in clusters, two to eighteen inches long, one half of an inch 
to one inch wide. Common along the New England coast. 
Genus Phyllitis 
P. fascia. Fronds light olive-green, leaf-like, three to six inches long, 
one fourth to one half of an inch wide; margin entire, slightly waved; 
contracted at base to short stalk; attached by disk. This species grows 
in bunches on rocks and stones at low-water mark, and is very common 
everywhere. (Plate X.) 
ORDER DESMARESTIACER 
(Named for M. Desmarest, a French naturalist) 
Genus Desmarestia 
D. viridis. Filaments cylindrical, about as thick as a bristle; branches 
opposite, in pairs, at intervals on the main stem. The branches branch 
again and continue to be disposed in the same manner. All are long and 
ultimately become very fine. The color is olive-green, becoming verdi- 
gris-green when exposed to the air for a short time or placed in fresh 
water. The species grows in deep tide-pools and below low-water mark, 
forming fine, feathery plumes, often a yard long, which give submerged 
rocks the appearance of a luxuriant garden. (Plate X.) 
D. aculeata (“spiny”). Fronds cylindrical at base, flattened above; 
branches long and straight, arranged alternately, when young beset with 
pencils of fine hairs, often one half of an inch long, which, later, fall off, 
leaving alternate spines along the edges of the flattened branches. It 
